NGC891 - Ha - 23rd Sept 2005

[Mike]

OK John said to have a go at NGC891 so here it is. This is a 35 mins in 5 min subs in Ha. I did the red channel and was starting the green when the clouds rolled over. So here it is in Ha for now and I will do the colour another night. This will be interesting to do with the Vixen.

[JohnP]

well..... what can I say except great! Can't wait for the full colour version - the extra mag & aperture of the vixen will really show it at its best. I'm determined to try this myself again at the next DSC. Thks for posting so quick.

Great shot (I Like it),   John

[Mike]

Take a look at this - I took my image and got an image of NGC891 from the DSS from 1989. I then aligned and resized them and then did a blink comparator in maximDL. There is a star at the top that has a HUGE proper motion. I've made an animated gif below so you can see. It is the star at the top in the middle.



By the way, I ran a PinPoint Astrometry analysis in MaximDL on the original image and it is saying there are stars down to Mag 21.4 in it !

[JohnP]

That's a very cool animation. Is yours the image with the less stars which are slightly more bloated? Is it normal for stars to move this amount or have you discovered something....? Perhaps you should submit the images to a recognized body BAA or something similar..? Who knows?

Great image & good work,  John

PS - Did you buy full licence for MAxim DL or are you still using demo?

[Mike]

Mine is the crap one of the two yes, but then the DSS image was taken with an observatory scope and I think is a scan from a film plate. Those images are 16 years apart so it will more than likely be the motion of the star. In 16 years if it was an asteroid or planet or something it would have moved a lot more, unless I just happened to image it around the same place in it's orbit.

I did indeed take the plunge and buy Maxim. I have found it so nice to use, the focusing routine in it is a breeze, the alignment features are excellent as well as the guiding features so I thought it was worth it. Getting stuff aligned in AstroArt was a nightmare and the ability to guide in AA is limited also.

[Mike]

John what happened to that TAL you have pics of on your website?

[JohnP]

HiYa Mike - I sold the TAL-2M the other day (no room) - I actually sold it to my brother-in-law so I still have access if I need it - only problem is it's in Oxfordshire...... Much darker skies than Bromley though

[Rocket Pooch]

Hi Mike,

I dowloaded the Maxim software and had a play against a set of RGB's taken on M33 on Tuesday night.  The software is great, very very easy to use.  

More than I can say for my RAW FITS files, there rubbish.  When I RGB image I get all kinds noise on the images, I actually think this is either light leak or the True Tek filters reflecting within the filter holder.   My OIII and Ha images are ok so I'm assuming its just going to be near impossible for me to do any good RGB from here.  Mind you I suppose I should not expect anything else at the moment from my location.

Chris

[Mike]

Well that's a shame. I read up about Blue Haloes round stars being caused by reflections on filters that are coated on both sides of the glass. The images you have been doing so far look great, especially considering your less than ideal location. I suppose light leak could be the cause - that imager's wheel has a big hole at the bottom that could let light in (and dust) if your workspace wasn't entirely dark whilst imaging. I guess to make sure you would have to cover it in a black cloth or something.

Yeah Maxim is so much easier to use than other software i've tried. A lot more intuitive too.

Anyway, any clear night if you'd rather pop round to my garden instead your welcome as i'm only 15-20 mins from you. Just give me a call. Theres a few trees to contend with but the light pollution isn't bad if the transparency is good and from different parts of the garden theres a good all round view of the sky (apart from NW, but that's in the direction of Bromley anyway)

[Mike]

OK I asked Jeff to investigate and he kindly did so. He has solved the mystery with this reply...

"The star in question is GSC 2839-01107-1, at magnitude 13.7. It appears to be showing a proper motion of 0.4" per annum, which is nothing out of the ordinary; Barnard's star shows a proper motion of 10.3" p.a. and Arcturus 2.3" p.a.

If you look over near the top left of the picture, you will see another star showing a detectable proper motion, GSC 2839-00703-1, at mag. 13.2. I have calculated this movement as 0.3" p.a."

Take a look at this image I found on the net. Some guy has taken an image of Barnards Star every 5 years and has taken 4 images to make an animation of its motion. This star FLIES across the frame!

[JohnP]

Impressive work Jeff - glad the mystery has been solved - I never realised Stars shifted position so quickly....

[Rick]

Doed this look a little familiar? It's from the Large Binocular Telescope.